This isn't the first time Siri has been part of a musical collaboration. Just a few days after the iPhone 4S launched, musician Jonathan Mann (perhaps most famous to Apple watchers for the Antennagate song that Steve Jobs actually played at a press conference) posted his own duet with Siri.

To my ears, all these musical experiments show is how far we have to go yet before computerized voices sound truly human. Siri does a much better job than the Mac voices of the mid-1990s did on songs like Radiohead's "Fitter, Happier," but the voicing still sounds very artificial in a musical context. We're still a long way from the vibrant, natural tones of 2001: A Space Odyssey's HAL 9000 and his rendition of "Daisy, Daisy."

Then again, with so many human singers over-utilizing autotune and starting to sound more and more robotic themselves, perhaps all we're seeing with Siri is the next step in a weird human/machine convergence in the music world.